All of the following examples correctly reflect concerns with selection bias, EXCEPT:
A) Those who refused to participate in the study may be different in some important respects from those who agreed to participate.
B) In a longitudinal study, some participants who started participating, later withdraw from the study.
C) Additional participants have been selected for the study when it was already under way.
D) Researchers have found out that those from more affluent neighborhoods have a higher response rate to the study.

Question

Quizplus · Accepted Answer

Option A, B, and D correctly reflect concerns with selection bias by highlighting potential differences between the participants and non-participants, attrition or dropout from the study, and differential response rates based on socio-economic factors. Option C, on the other hand, does not reflect selection bias, as additional participants being selected for a study does not necessarily lead to bias unless the selection criteria or process itself is biased.

All of the Following Examples Correctly Reflect Concerns with Selection